How Many Instagram Accounts Can One Device Have?by David Wayne
Instagram doesn't place any limit on the number of accounts you can create, as long as you provide a different email address for each one. The Instagram mobile application supports signing in with only one account at a time, although third-party programs enable you to manage multiple accounts from a single interface.
Creating Multiple Accounts
From the Sign In screen, tap “Register” to create an account. If you're already signed in with your current account, tap “Settings” and select “Log Out” to go to the Sign In screen. Unlike many e-commerce sites such as eBay and PayPal, Instagram doesn't link your accounts to an IP address or device, so your logging out and creating multiple accounts isn't monitored or detected. You can create free email accounts with services such as Gmail, Yahoo and Zoho (links in Resouces).
Account Management Software
To log into multiple accounts simultaneously, you need third-party software, such as Fotogramme, Multigram or Padgram (links in Resources). While each of these programs supports switching between accounts and viewing multiple account feeds, only Padgram enables you to upload pictures to your various accounts. Since Padgram is only available for Android devices, iOS users must upload photos to multiple accounts using the Instagram application.